When I first set eyes on Kanye West I don't recognise him. Waiting in the grandiose foyer of the Grand Hyatt in Tokyo (younger sibling of the Park Hyatt, the setting for Sofia Coppola's film Lost in Translation), I'm suddenly confronted by a trio dressed in a riot of fluorescent pastel hoodies and box-fresh sneakers. Slowly, I realise the figure in the middle, hidden behind cherry red Louis Vuitton shades, is the self-styled 'Louis Vuitton don' superstar rapper himself. His partners in fashion crimes are tour manager Don C and stylist Ibn (pronounced Iben), who will seemingly never leave Kanye's side over the six months that - on and off - I spend with them.

As we leave to travel to tonight's gig in Yokohama, Japan's second largest city, 20 miles to the south, Don C says to me, 'Yo, you can ride with us.' I end up near the back of the people carrier with Kanye as we nudge through Tokyo's traffic on a muggy spring afternoon. 'So what are y'all listening to in England?' he asks. I mention a few names including Dizzee Rascal and Arcade Fire. 'Man, I don't really get the Arcade Fire thing.' He shakes his head, a little puzzled. 'I been listening to it on my iPod, trying to understand why people get off on it, but I just don't get it.'

Kanye reaches into his Louis Vuitton backpack and pulls out a CD-R of his embryonic new album and passes it forward. He may not be the bestselling hip hop artist in the world - although on this short tour of Japan, he's recognised by fans everywhere - but he is the most critically feted. Graduation will complete the trilogy started in 2004 with The College Dropout and followed in 2005 by Late Registration. Given the multi-platinum success of those records and hits like 'Gold Digger', the pressure to deliver a masterpiece that will reach an even broader range of fans and win further plaudits is properly on already.

The vehicle's audio system is a ridiculously complex affair controlled by a digital screen with which the driver doesn't seem too au fait. There's a little bilingual banter before someone suggests the red light may mean it is recording, and the atmosphere sours a little. 'Yo, does that thing have a hard drive?' says Don C in a manner that leaves little lost in translation. 'Don't be recording this, don't press record!'

'Yo, you better be ready to press eject!' pipes up Kanye.

The CD finally starts playing, and a new song called 'Good Morning', with ethereal gospel backing vocals, emerges from the speakers - but the sound is dreadfully tinny. 'What's up with the bass?' complains Kanye, as someone tries to adjust the levels. Outside, the traffic slows again and an irate Kanye gestures at the taxi behind carrying the record company PR and OMM's photographer: 'I bet that cab has a better system, man.' I presume he's joking, but as we turn onto the slip road to the Bay Area Freeway, he leans forward and shouts, 'Yo, stop the truck!'

Seconds later, I find myself on the side of the freeway with Kanye as the traffic whistles by. 'Damn! Welcome to my life, man,' he exhales as he jumps in the passenger seat besides a startled taxi driver and starts fiddling with the CD player.

When he finally gets it working, Kanye whacks the volume up full so the speakers are almost popping. Impressively, the silver-haired taxi driver, at least 65 and immaculately presented in full suit and white gloves, doesn't flinch once. The next track is called 'Stronger' and starts with an instantly recognisable Daft Punk sample, the vocodered 'Harder, Better, Faster, Stronger' from their 2001 album Discovery. 'You know that sample, right?' shouts Kanye over the music. He starts to bounce back and forth so violently his seat begins to rock, before he turns the volume down slightly to explain that he hasn't recorded all the vocals yet. 'I just finished this verse on the plane over yesterday,' he says, before pushing it back up and turning round to rap, full throttle, into my face:

'Let's get lost tonight/

You can be my black Kate Moss tonight/

Play secretary on the boss tonight/

And y'all don't give a fuck what they all say, right?'

It's difficult to know where to look. Unless you're the taxi driver, whose eyes stay fixed straight ahead. Even through the distorted speakers, the track does sounds pretty incredible.

'Damn, they don't make 'em like this any more,' Kanye continues rapping in my face: ' ...bow in the presence of greatness.'

Almost everyone I spoke to before meeting West mentioned his arrogance, although he would have you believe it's more self-belief. An only child ('Kanye' is an Ethiopian name which means 'the only one'), whose parents split before he was a year old and who divorced when he was four, Kanye was mainly raised by his doting mother, Donda. They are still extremely close; he wrote a song for her on his last album, 'Hey Mama', which, sweetly, she now has as the ringtone on her cellphone. When Kanye was still a young child, they moved from Atlanta, Georgia, to Chicago, where she became the chair of the English department at Chicago State University before latterly taking over as his manager. She has just published her own book, Raising Kanye: Life Lessons From the Mother of a Hip-Hop Superstar, in which she writes at length about how she nurtured his confidence (see below).

Maybe it's the result of no one else having heard tracks from the new record, but when we meet in Japan Kanye's self-belief doesn't seem quite so solid. After playing me 'Stronger' he says of the line 'I need you right now': 'If you heard that in a club you might be looking at a girl thinking "I need you right now" but it's also a message from me to my fans that I'm coming back after a time away and I need you right now, to help me come back.'

The soundcheck in Yokohama involves DJ A-Trak - aka Alain Macklovitch, the youngest ever winner of the DMC World DJ Championship - spinning the CD-R of the new tracks while Kanye stands by the decks, rapping over the top. There's 'Homecoming', a collaboration with Chris Martin, based around a piano motif on which the Coldplay frontman sings, 'Do you think about me now and then?/ 'Cause I'm coming home again'; a track called 'The Good Life' that samples Michael Jackson's 'P.Y.T.'; and a moodier number about messing with 'drunk and hot girls', which, I find out later, is called 'Drunk & Hot Girls'.

We retreat to Kanye's dressing room and Ibn cuts his hair. 'I want lightning bolts going in different directions,' explains Kanye, demonstrating with his fingers splayed across his skull. As Ibn gets to work with his clippers, Kanye and A-Trak discuss Graduation with surprising frankness. 'All I'm saying,' A-Trak shrugs at one point, 'is where's your 'Diamonds'?'

I suspect the DJ is one of an extremely select few allowed any criticism of Kanye. The star listens patiently before putting forward his own views. Then he catches a glimpse of his head in the mirror. 'I said lightning!' he exclaims. 'You put points on the end of 'em - it looks like I got arrows all over my head!' Kanye West made his name producing beats for other rappers, kicking off with 'This Can't Be Life' for Jay-Z's The Dynasty album in 2000. But although his signature sound, involving speeded-up soul samples, was widely acclaimed, his 'Preppy' look and middle-class background meant he struggled to be taken seriously as a rapper in his own right; several record companies turned him down before he landed a deal with Jay-Z's Roc-A-Fella label.

A near fatal car accident in 2003 inspired his debut single 'Through the Wire', which he recorded with his mouth wired partly shut following the crash. Since then, unusually for a contemporary rap star, he has spoken out against homophobia in hip hop and tackled politics in his lyrics. His persona is far more complex than most of his peers, but not without its contradictions. When he signed his deal with Roc-A-Fella he went straight to every US rappers' favourite jeweller, New York's Jacob the Jeweller, and spent $25,000 on a necklace - then highlighted the plight of West African children mining precious stones on 'Diamonds from Sierra Leone'.

He works at a furious pace, intent on embracing fields outside of music. He oversees the design of all his artwork and videos, is in the process of launching his own clothing line Pastelle, and has even started work on his own TV show with Seinfeld writer Larry Charles. 'We're editing the pilot right now,' he confirms, though he doesn't want to reveal much more.

There's little chat on the way back to Tokyo, as everyone is jetlagged and falls asleep. The next morning we meet in the foyer again. West is off to see acclaimed contemporary artist Takashi Murakami, the 'Warhol of Japan', who is directing the artwork for the whole Graduation project, from album cover to animation and T-shirts. Murakami's offices are a short drive away in Roppongi Hills, but when we arrive Kanye suddenly decides his entourage is too large, and we're asked to wait in the people carrier for a while. Which we do. For five hours. Eventually, word is sent down that I can join him upstairs, where he is working - through an interpreter - on T-shirt designs with one of Murakami's team.

In Raising Kanye, Donda recalls buying her three-year-old son a box of Crayolas, and how, even though his talent stood out even then, he would always put his own stamp on things. 'He rarely made things the right colour. He would make the banana purple and the orange blue.' Little seems to have changed. Kanye gets increasingly frustrated when the pastel camouflage design doesn't match his vision. 'No, no!' he complains to the interpreter, almost stamping his foot in frustration. 'Tell him no orange in it!'

'I definitely have OCD [Obsessive-Compulsive Disorder],' he nods, when I bring up his tendency to obsess over details later. 'I have to be creative at all times and I have to learn. I don't know any other way. I'm a designer and rap is just one of my designs.'

Do you find if difficult to switch off, to have a life outside your work?

'My life is work. My career is a labour of love. It's not like I wanted to leave Murakami's studio ... I wanted to stay as long as possible.'

Since the release of Late Registration, he has found himself in the public eye on two particularly memorable occasions. Three days after the album's release, on 2 September 2005, he appeared on live TV for a benefit concert for victims of Hurricane Katrina. After going off-message and complaining 'I hate the way they portray us in the media. You see a black family, it says, "They're looting." You see a white family, it says, "They're looking for food,"' while his co-host Mike Myers looked on like a rabbit in the headlights, he concluded, simply, 'George Bush doesn't care about black people.'

Less edifyingly, at the MTV European Music Awards last November, Kanye stormed the stage when the Justice v Simian's 'We Are Your Friends' beat his own 'Touch The Sky' to the best video award, grabbing a mic and declaring: 'Fuck this! My thing cost a million dollars man ... I had Pam Anderson, I was jumping across canyons and shit. If I don't win, the award show loses ... credibility.'

We discuss both events in Japan en route that second day to Springroove, an indoor festival that Kanye is headlining. The bill also includes Lauryn Hill, Lupe Fiasco, Ziggy Marley and Lady Sovereign, as well as Japanese artists such as the Teriyaki Boyz.

'I'm an artist that people love to hate,' he shrugs. 'Even if they love me sometimes they just like to talk shit about me, because there are very few artists who stand up for what they believe in.'

Even five months on he is, however, aware he overstepped the mark at the MTV awards and that many people were sick of his shameless ranting, although he would like to make it clear he had been told beforehand he would win the award and felt stitched up by the organisers. 'It's important to express my opinions,' he explains, 'but I need to learn that sometimes it's not the right time to express yourself.'

The venue that night is a soulless enormadome, but Kanye still manages to get the crowd whipped up getting by far the greatest response of the evening. After the gig we travel to the super-fashionable and futuristic Shibuya area to shoot West against a backdrop of neon lights. It's gone 1am, but the streets still throng with fabulously dressed Shibuya boys and girls. Many recognise Kanye, but most keep their distance. He has decided to keep his white headphones on for the shoot, which I presume he's just wearing for a prop, until he wanders over to me in-between shots. 'Man, I still don't get this Arcade Fire thing.'

The morning after we arrive, Kanye joins his mum for a book-signing for Raising Kanye at the Madison Square branch of Borders. The signing is not nearly as busy as I expect it to be, but there's still a queue of fans, most bearing gifts, from bouquets of flowers for Donda from female fans ('You must be so proud') to odder presents like a terrible oil painting of her son. Several hopeful rappers try to pass on demos to Kanye.

'Yo, can you tell people not to try and pass him stuff?' Don C asks a security guard.

'He's here for his mom, to support his mom,' stresses Ibn.

'People don't care about that,' says a nearby fan. 'People will try and give people demos at a funeral. It's a tough business, you gotta do what you gotta do.'

After the signing, we shoot across midtown to the studio of the creative team busy with the graphics for the video to 'Stronger'. Directed by Hype Williams, it is an epic affair, three months in the making, featuring a genuine Japanese motorcycle gang. A dozen designers are working on effects like the red trail left by a motorcycle brake light, and the words, 'Harder, better, faster, stronger'. Kanye pads around, scrutinising the screens. 'This is interesting, right?' he asks me, rhetorically. 'Not many rappers do this shit.' The two of us watch a scene where the half-naked Kanye is engulfed by an animated machine, Akira-style. What exactly is the machine doing to you, I ask. 'I dunno,' Kanye shrugs, 'just ...'

'Making you harder, better, faster and stronger?' I venture.

'Yeah,' he grins.

That evening he has to film a couple of final close-up shots for the video at a convention centre near Chelsea pier. We arrive at dusk just as he and Ibn arrive with three full suitcases - one full of sneakers, the others full of jeans, T-shirts, hoodies and jackets. The two of them pick out a couple of outfits and then Ibn takes a photo of Kanye to show him what he looks like. During a break in filming, Kanye wanders over and perches himself next to me, munching on a grilled chicken sandwich. He talks about the reaction to 'Can't Tell Me Nothing', which is being used as a lead single in the States. It's proved more popular 'in the hood' than any previous Kanye track. It's clear that if there was a slight crack in confidence when we met in Japan, it's gone now. 'People say to me, "What do you mean, coming back with a song like that?"' he chuckles. 'I said: "That's exactly what I mean: you can't tell me ... NUTHIN!"' He almost growls the last word.

The following night it's the birthday party. The venue, naturally, is the Louis Vuitton store on East 57 Street. The whole block is gridlocked with ostentatious vehicles including a host of blacked-out SUVs, a cream coloured Rolls Royce, mayonnaise-coloured Benz and a bright red Lamborghini. Inside, it is packed - just moving up the cantilevered staircase one floor can take 20 minutes. Bartenders pour liberally from bottles of Hennessy and champagne. It's a heavy-duty guest list, with most of Kanye's peers and New York's music royalty in attendance, including Jay-Z, Rihanna, Mariah Carey, P Diddy, Fall Out Boy, Ashlee Simpson, Common, Swiss Beatz, Jermaine Dupri and Russell Simmons.

Kanye is dressed in a dinner jacket and bow tie, with jeans and sneakers. He seems penned in and every time he moves, the crowd moves with him, so I'm surprised when he makes his way over and greets me with a hug. 'Great party, huh?' he asks.

John Legend and the Clipse both perform short sets before Kanye takes to the small stage and thanks everyone for coming, before speeding through a couple of numbers himself with Pharrell Williams, Fabolous and Lupe Fiasco. The venue is so packed only a few at the front can see, but I do glimpse doting Donda dancing at the side of the stage.

Three weeks later, Kanye makes a flying visit to the UK to perform at the Concert For Diana and the Manchester International Festival. Straight off a plane from Paris, he heads to another Raising Kanye signing at Waterstone's, Piccadilly. The surrounding streets are still closed after the failed car bombing on Haymarket the previous morning. 'I don't think they were trying to bomb me,' says Kanye when I ask him later if he's concerned. 'When it's your time to go, it's your time to go. If something is going to happen to me, I'd rather it happened while I'm performing, or giving back to the fans, while I'm doing what I love.'

The following day is the Concert For Diana at Wembley Stadium. It seems slightly odd that Kanye West is on the bill - not only is he easily the edgiest artist, there's also the matter of his own near-fatal car crash - but he isn't surprised himself (although he later tells me he was asked to remove a couple of chase scenes from the videos screened alongside his performance). He takes the stage in the late afternoon, and while everyone else has sung two or three of their best-known tracks, he storms through a montage of 'Gold Digger', 'Touch the Sky', 'Stronger', 'Diamonds' and 'Jesus Walks', comprehensively stealing the show. During 'Touch the Sky', he sprints from one side of the Wembley stage to the other while rapping breathlessly and the TV cameras show audience members mouth agape. The comparison couldn't be greater with P Diddy, who follows Kanye with a drawn out p.diculous performance of 'Missing You' which he dedicates to Diana who was 'so beautiful, so graceful, so compassionate, so Royal ...'

It's also the first time the UK gets to see Kanye's latest fashion statement - his shutter shades. Even the Princes are moved to comment when Kanye meets them after the show. 'One of them said: "I thought those glasses were bling" and the other one said: 'It's Kanye West, they'd have to be bling,"' he chuckles later. 'I didn't have the heart to tell them that I'm the anti-bling.'

Even though a version of 'Stronger' has already gone to radio, he's spent the last couple of days tweaking it further. He's now worked on the track with eight different engineers around the world, and recorded over 50 versions. After his outburst at the MTV Awards Kanye went back and discovered Justice's music and ironically, the influence and connections of Justice and their forebears Daft Punk now help Graduation feel right on the zeitgeist. 'I think God had me not win that award for a reason,' Kanye agrees, 'He was like, "Hey, let me introduce me to your new friends."' A friend of Justice, the designer So Me, who was on the podium with them that night, has just directed the video to West's next single 'The Good Life'.

Would he agree Graduation introduces a harder edge to Kanye West? 'Well, I think it's a bigger sound,' he clarifies. '"Stronger" is more of a stadium thing, a throw-your- hands-up-in-the-sky vibe. It still has heavy melody, but we played with the drums a lot. We spent weeks on the drums on "I Wonder" [the album's opener]. "Stronger" doesn't even have a real snare, it's like a digital open hi-hat. Just to play with those things in the rap world is really interesting.'

The release of Graduation has been put back a week, which means it will now come out on the same day as the new album from 50 Cent, the biggest-selling rapper of the millennium. Kanye assures me he isn't bothered by the clash. 'It's better, isn't it? It makes it more of an event.'

Even if it means you don't go to number one?

'It's more important for me to be involved in an event than to say I had a number one album. If I come out on a week no one else is out and go to number one people will be like, "Whatever ...", but if I come out the same week as 50 and go to number two people will be like [excited], "How close are the numbers? I need a recall!"'

While his label boss Jay-Z's rhetoric has always revolved around him being a hustler, who now simply hustles in the rap game, Kanye prefers to constantly refer to himself as a designer, who happens to design raps. When Graduation is finally finished, Kanye has plenty of other designs to work on. He's working with Madonna's choreographer on plans for a spectacular tour, which should reach the UK in the new year. His clothing line should launch soon, not to mention the TV show.

One of the biggest revelations for me over the past few months is that if you learn to either accept or disregard his arrogance or ego, and have the energy to try and keep up with his relentless drive, Kanye himself is very engaging company. 'The biggest misconception is people think I wouldn't be cool to hang around. I think I'm a cool guy to hang around, but then maybe that's just me being arrogant again,' he chuckles, 'I'm not saying it's a misconception that I'm cocky. I am cocky. But as you've seen most of the time we're laughing and joking and shit.'

He talks again of how the visuals, and in particular Japanese graphics and design, have had a heavy influence on this album, and how the imagery and music feed off each other. Which takes me back to a late-night conversation we had in Japan.

'I have neon lights in the studio now,' he had said. 'People always used to say I didn't know how to set a mood in the studio because even though I made soul music at that time - I mean, my music is still soul, but, you know, quote unquote soul - I never lit candles and shit. But now I have my neon lights ... when they said I never knew how to set a mood before, I never really had a mood before that fitted with me.'

Before now?

'Before now. But now I got the neon lights and I'm like, OK, I like this mood right here. It's like when I was a little kid, I was hip hop before I knew what hip-hop was, they couldn't find a label for me, the way I dressed, because in Chicago, no one dressed the way I dressed ... but now I know what it is.

Now I know my mood is neon.'

He paused and considered this.

'I AM neon.'

You are neon?

'I. Do. Glow. In. The. Dark.'

And that's what you want the music to do?

'Yeah.'

· The single 'Stronger' is released August 13, and Graduation is released on 10 September, both on Mercury

How the West was raised

'When Kanye was six, my sister and brother-in-law took him to a lake. There were ducks there just quacking away. Kanye took exception to the way the ducks were quacking. "That's not the way they're supposed to sound," he said, and started quacking the way he thought it should be. Now those were real ducks quacking and he felt like they were doing it wrong. In his mind it should have sounded a different way. He was adamant that the ducks were quacking wrong. Kanye had a distinct perspective. He always had his own spin on things. I never criticized him for it. I figured I would just nuture the creativity ...

'When he was 12 or 13 I caught him primping in the mirror one day. He turned and said, "Mom, look at me! I could be a teenage sex symbol!" He was serious. It used to tickle me, him looking at himself in the mirror. And Kanye did become that sex symbol. You have to be able to see yourself; you have to be able to see it when no-one else can see it. You have to visualize where you want it to be and claim it. Kanye claimed it a long time ago. Those countless hours in his room, the years of preparation, prepared him for when his vision finally came to fruition.'

Donda West

· Extracted from 'Raising Kanye - Life Lessons From The Mother of A Hip-Hop Superstar' by Donda West (Simon&Schuster)